Problem using analog feedback on pix7340

Hi,
I am trying to use analog force feedback on one of my axis on pxi 7340. The problem is that MAX always uses encoder as feedback even if i configure it to be analog. In MAX i disabled encoder and enabled the appropriate ADC for the axis and set the position to few hundred counts so the controler stops the axis when force is above a small value (around 1V). If i start motion it moves the same as if the feedback was encoder (for few hundred counts). I dont know what is happening. I red the motion manual and if i understood it correctly the axis should move at the configured speed until the force is larger as value i set in position field.
Thanks
Solved!
Go to Solution.

Hi toni939,
please have a look at this document to get a full understanding how analog feedback works with NI motion control boards. I have also gathered all discussions with my involvement about analog feedback under the AnalogFeedback tag.
Kind regards,
Jochen Klier
National Instruments
Message Edited by Jochen on 02-03-2010 04:20 PM

Similar Messages

Trigger based on Position when using analog feedback

I am developing an application that uses two hydraulic cylinders to move a model in a pitching and plunging motion.
My hardware consists of a P4 computer running windows XP SP2. The motion controller is a PCI-7350, 2 axis board.
The two hydraulic cylinders are equipped with analog position sensors which provide the primary feedback signal for the motion control.
The drive signal from the motion controller is used to open or close a hydraulic valve, closing the loop. The motion portion works great.
I am using buffered contouring to generate a precise motion on the two axis using a vector space. The update rate is 10mSec and the motion appears to be correct. Is the contour update rate a precise 10mSec if the PID is running at 62.5 uSec?
My problem is I need to generate a trigger when the controller is on specific positions of the contour. I can't use breakpoints as I am using analog feedback instead of an encoder. I wrote an onboard program that monitors the contour buffer and toggles the breakpoint line when the controller is on or beyond the specific point. It runs ok and is close but, I am getting an occasional timing discrepency of roughly 16 mSecs. ie the trigger will occasionally be late by more than 1 contour period.
I tried increasing the size of the buffer to hold all the points as I thought the delays might be occuring when the buffer was being updated. No change in performance. I tried assigning more time to the trigger program as it is the only on board program, but again it seemed to make no difference. I reduced host communications to a minimum, no change.
I have attached my entire application and a test sample waveform in a zip file. You can run the application without any hydraulic cylinders if you set max following error to 32768. You should have a trigger pulse on the breakpoint line every 500 mSec.
Any pointers would be greatly appreciated.
Attachments:
M22PitchPlunge.zip ‏524 KB

Brian,
Yes, you can reach exactly 10 mS update interval with a PID rate
of 62,5 µSec. You can calculate the actual interval with the forumla
provided here.
Of course the accuracy is limited by the accuracy of the onboard
oscillators of the board but this shouldn't be really relevant.
Generating triggers based on 2D position data is not a trivial
task. I have tried to examine your program but it's a bit hard to read.
I had a look at your onboard program. I don't understand exactly how
you determine if the axes have reached a trigger position or not. It
looks like you are only reading values from buffers. For an exact match
with the physical positions you should read the real position values
from the axes and compare them with your trigger position buffer. In
your comparison algorithm you will need to add some tolerance to allow
some deviation from the ideal trigger position (see image).
There are several possible solutions for your application. You could
either try to implement the more advanced comparison in your onboard
program but I'm not sure if this will result in the performance you
need. The 7350 provides only a limited amount of CPU power for onboard
programs. At last it all comes down to the question how good your
deterministic real-time behavior needs to be. If some ms delay and
jitter are ok for you then you probably could stick with this approach.
If you need a better real-time behavior you should consider using
either an additional real-time board like the PCI-7041/6040E that could run the 2D trigger algorithm or a PCI-7830R board that could run the algorithm on an FPGA.
There are even more options including the NI SoftMotion Development Module to design your own motion controller using LabVIEW RT but again, this depends on your application needs.
Best regards,
Jochen Klier
National Instruments Germany
Message Edited by Jochen on 09-09-2005 10:47 AM
Attachments:
Image1.jpg ‏19 KB

Problem when analog feedback is set as primary feedback

I have a simple labview program for pressure control. Primary feedback is set to ADC 1 in MAX. ADC 1 is connected to a voltage signal which represents a pressure. When the motor run from program, the motor stopped after certain time because move complete turn to True, but the position reading didn't reach the desired position at this time. If the motor run from MAX, the motor didn't stop untill the position reading reached the desired value.
The configuration file exported from MAX and lv program are attached. I would appreciate you very much if anybody could find problems in my program or configuration.
I am using PCI 7342.
Thanks.
Attachments:
ADC_primary_feedback.xml ‏581 KB
pressure_control_2.vi ‏74 KB

Hello Ya-hoo.
I first just want to clarify what I think your issue is. It sounds like you essentially have a servo motor system with analog feedback. This system is moving to the desired position (pressure) when it is run through 1-D interactive in MAX, but it does not correctly move in your LabVIEW program.
This situation is uncommon but it can happen. Generally speaking, the things to make sure of:
Be sure the settings are saved in MAX and that the board is initialized with those settings before running the LabVIEW program
Make sure you are not calling the stop VI too early. In the while loop you are polling the move complete criteria. What happens if you take that out and simply wait until the user pushes the stop button? If this fixes
the problem, try adjusting some of the Move Complete criteria (Trajectory Settings in MAX) and see if that changes the behavior.
As far as the tuning is concerned, I will refer you to the following tutorial on Understanding Servo Tune. This should go over some tuning concepts.
Hope this helps.
Regards,
Colin C.
Applications Engineering
Colin Christofferson
Community Web Marketing
Blog

Torque control is not working for my system using analog feedback

In the test bed, we are testing a brushless DC motor and a load motor generates torque to the test motor. The test motor is running with torque control scheme. They were connected together and I measured the torque signal to feedback the signal and control it. However, I just realized it only control when the torque was static. If I commanded a certain torque value (in this case, counts command), it kept generating that value. However, it did not generate the same torque in different position. I heard NI motion controller could develop torque values by mapping the torque signal with encoder signal. If it's true, the torque generation based on analog feedback, also, needs constraint by rotor position, right? W
hen I turned on the load machine with constant speed (50 RPM), the torque from the test motor did not provide the constant torque that I commanded. It generated the fluctuated torque values. This means the max torque was generated at one point and decreasing by rotating the shaft and increasing the torque. Keep going in this way. Could you please tell me if this is the correct response when we are using analog torque feedback?
Thank you.

Try the following:
1.-Set your test motor to encoder feedback instead of analog feedback.
2.-Load a velocity move on the axis for the test motor.
3.-Set the following error limit on you axis to 0 (disable following error).
4.-Use the load torque limit function to limit the amount of torque the 73xx PID loop will generate,this value is in volts, so you will need to do a correlation between the voltage output from the controller and the torque reported by your torque cell.
5.- Start the load motor.
6.-Engage the cluch.
7.-Start the velocity move on the test motor, you will see the torque ramp up to the torque limit.
8.-Call the load torque limit function on the fly to vary the torque setpoint to where you want it.

Samplerate problem using Analog In and Counter In from a NI 6259 USB. "Counter timeout" setting in DAQmx?!

Hello,
I got a fundamental problem with the correlation of the timer settings of the DAQmx driver in DIAdem DAQ. I dont know where the problem is located exactly but maybe someone can help me if I explain what happens:
In my configuration I use some analog inputs from a USB 6259 with 20kHz samplerate and two counter inputs for frequency measuring via DAQmx in DIAdem DAQ.
There has to be an extra DAQin block for the analog inputs and the counter inputs with also an extra "Clock"-block for each of them. The clock of the analog inputs runs with 20kHz hardware clock and the other one with 10Hz software clock because the hardware clock mode is not allowed or supported.
My problem is the display refresh rate in VIEW. If the counter signal has no input (because the measured system is not active) the display seems to wait for any input and doesnt refresh the analog values on screen. If the system is active and a rectangle signal is seen by the counter in, the display refresh rate raises and the frequency value is displayed more or less accurate. Has that something to do with the counter timeout setting in the DAQin driver options block (marked in the attached image)? If i decrease the timeout, the display refresh rate gets better but not as good as without using the counter inputs in my DAQ diagram. I think the counter input is not as easy to handle as the usual analog inputs... I only want to see the measured frequency on the display during the measurement without getting any influence on the analog input channels and their displaying.
The other problem is the display and the measurement of the frequency itself. If i check the function of the counter input in the Meas. & Automation Explorer the frequency is display correct without any dropouts or something like that. The signal I measure in DIAdem on the other side looks quite bad because there are spikes of some MHz and even more although the measured range is between 20 and 80Hz!
Has anybody made similar experiences?
Regards
S. Zimmer
Attachments:
probs.png ‏112 KB

Hi there,
it seems that german is your mothertongue, so I'll reply on german.
Digitale Eingänge müssen Software getaktet werden, da nur analoge Eingänge Hardware-Takt Unterstützung haben!
Sie können den Hardware-Takt nur mit analogen Eingängen einsetzen, die, von einem Timer gesteuert, gepuffert Werte einlesen können. Digitale Größen verarbeitet der Hardware-Takt nicht.
Mit dem Hardware-Takt erreichen Sie sehr hohe Abtastraten. DIAdem überträgt die gewünschte Rate und die Kanalliste auf die Karte und startet die Messung. Die Hardware erfasst die Daten selbstständig und sammelt die Daten. Der PC ist nur für den Abtransport und die Weiterverarbeitung verantwortlich.[...]
Da digitale Signale nicht im Hardware-Takt erfasst werden können, müssen diese Signale parallel in Software-Takten ermittelt werden. Dies kann zu zeitlichen Verschiebungen führen, weil sowohl beim Start der Messung als auch während der Messung keine Synchronisierung der Timer im PC und im Messgerät erfolgen kann. Da zwei Timer nie ganz genau gleichzeitig gestartet werden und auch nie ganz genau gleich schnell laufen, stimmen die Zeiten in den Zeitkanälen nach der Messung nicht genau überein. Üblicherweise betragen die Abweichungen einige Millisekunden.[...]
Weiters hab ich mal n Versuchsaufbau für die Frequenzmessung gemacht. Ich konnte problemlos Frequenzen messen...
Am besten du schilderst kurz den Aufbau deiner Messung, was du messen möchtest und wie du den Max konfiguriert hast.
Mfg Markus

Analog feedback 7344 0-5V non liniar

Hi.
Having a 7344 left over from an aborted project, I wondered if this controler would accept a non liniar 0-5V position feedback in PID closed loop.
I know the analog input is "only" 12bit, but this gives by far the required position on the travel I need for this application which is to be an automatic throttle control on my enginedyno. It is not possible (nor practical) to mount encoders on the many different throttlesystems, so the 0-5V from the throttlepositionsensor is all I have.
If ok, then what kind of motor should I look into, stepper og servo since the application is more still standing in any position than actual turning (running is expected to be very few turns when geared to move throttle 0-80 grd. I have both a SX and CX Nudrive.
Thanks in advance
Peter Rene

It should be possible to use the 0-5V signal as an analog feedback. You can configure the ADC settings for a 0 to 5 V range that maps the full 12 bit resolution to your feedback range. For position control it doesn't matter that your feedback signal is non-linear as long as you know how the voltage of your feedback signal corresponds to the position of the motor. Still you will see the same amount of non-linearity in the velocity profile of your axis as long as you don't run your axis always in contouring mode to compensate it.
Even though most time your axes are static which I agree would suggest to use a stepper I recommend to use a servo instead. The reason is the fact that closed loop steppers are not controlled in the same way as servos. In theory, analog feedback for stepper motors should work correctly; however, there are several problems that will arise when you attempt to control a stepper motor from an analog feedback. In this type of system, the analog feedback is converted into a position and compared against the desired position, and then the stepper motor is "pulled in" to that position. One of the problems with analog feedback for stepper motors is noise, another one are non-linearities of the feedback signal. Closed loop stepper mode relies on a fixed ratio between the generated steps and the feedback. This is not the case if the feedback signal is non-linear. Thus you will have to use a servo motor.
As an alternative you should consider using a stepper motor in open loop mode (without feedback). If you can make sure that you don't loose steps this would be the best and easiest option.
I hope this helps,
Jochen Klier
National Instruments Germany

Is there and easy way for Position control using analog input?

Hi Everyone,
I would like to set one of the axis with stepper motor using analog feedback to keep the set position which is coming from the analog input.
In other words I would like the stepper to move when the analog input changes. I need it as a "background service" so the rest of the motion could be easily controlled from the NI-Motion Assistant.
Is there any easy way to do this? Even complicated is ok but the control should be done by the NI Motion card not the PC processor.
Thanks,
Andras

Hello Andras,
please use the link below to get the motion example.
http://zone.ni.com/devzone/cda/epd/p/id/353
Kind regards,
Elmar

Is it possible to condition a load cell signal with a 1520 SCXI and then use it as the primary analog feedback for a 735X motion control board?

My system
PXI 1052 chassis
PXI 8196 RT controller
Flexmotion 7356 motion controller
Flexmotion 7354 motion controller
6259 M series DAQ
1520 SCXI
1520 SCXI
1314 SCXI frount mounting terminal block
DSM strain gage load cells
Exlar SR Brushless PM motors
Kollmorgen servo star CD series 5 drives
My objective:
I want to measure the force on the load cells with the 1520 SCXI (i.e. excite the load cell then amplify and condition its output) then I want to use this analog (force) signal as the primary feedback for my motion control system (7356 and 7354 motion controller connected to my drives and motors).
The problem:
The motion controller boards (7356 and 7354) can be configured for force feedback control via analog feedback from a load cell. However the boards implicitly expect the load cell signal to be amplified and conditioned with and external signal conditioner rather then using an NI SCXI module. Currently I’m am reading the SCXI signals via the 6259 M seriers DAQ and consequentially have no way to route the signal into the 735X boards for force feedback control. I can use softmotion to control the motors but then I loose the fast PID update rates possible with the 735X boards.
The question:
Is it possible to condition a load cell signal with a 1520 SCXI and then use it as the primary analog feedback for a 735X motion control board?
Thanks
Patrick Aubin
Ph.D Candidate
University of Washington &
VA MedicalCenter of Excellence for
Limb Loss Prevention and Prosthetic Engineering

Hi GG,
Thank you for your feedback.
>create your own external circuitry to amplify the signal.>
True a few op-amps could amplify and filter the signal externally but the performance of such an amateur built system will never match the accuracy and functionality of the 1520 SCXI. That’s why we spent the $2500 for the professional version.
>One thing that you could do is to use a UMI with your motion controller and then wire your signal from your SCXI to the UMI.>
As I understand it the UMI is basically a break out connectivity interface for third party drives. After conditioning and amplifying the analog force signal with the SCXI module the analog signal isn’t available to wire into a UMI. To my knowledge the conditioned signal of the SCXI resides only in the PXI backplane (i.e. there is no physical access to the conditioned analog signal). Can you explain how the UMI could be help here.
Again thanks for your input GG.
Patrick

Feedback problem using

I'm using the Room EQ Wizards software to test my sub. This works by connecting an SPL meter to LINE IN and connecting the sub to LINE OUT on the soundcard. My soundcard is an USB soundcard Creative SB Connect, Optical Digital I/O, model no SB0270, also known as "MP3+" I think... A picture of it can be found here:http://www.komplett.no/img/p/200/327240.jpg?The problem is that I get feedback and I cannot see why. Well, I can see why (if there's some kind of monitoring turned on in the soundcard), but I cannot see how to turn it off. IS there a way to turn it off? It's not like I can mute LINE IN, because I need that input!?Please HELP ME!

Hi toni939,
please have a look at this document to get a full understanding how analog feedback works with NI motion control boards. I have also gathered all discussions with my involvement about analog feedback under the AnalogFeedback tag.
Kind regards,
Jochen Klier
National Instruments
Message Edited by Jochen on 02-03-2010 04:20 PM

Encoder and analog feedback together

I am using a PCI 7344 board that will operate up to 4 axis with both encoder and transducer feedback.
The user will have the ability to switch between the two types of feedback whilst on the fly with the system momentarily executing a stop command before re-configuring itself in the other mode be it encoder or transducer. This works fine.
My problem is - when I am in encoder feedback mode, I do not get a feedback reading from my transducer as my primary feedback device is the encoder and as such the output given is for the primary device. I need to be able to see the analog feedback device whilst operating with the encoder and primary feedback.
I may have a solution to this, by using one of the feedbacks as the secondary feedb
ack although could not find any information regarding secondary feedback on NI's web site.

Hello,
First of all, analog feedback can not be used as secondary feedback. When you are running on analog signal as your primary feedback, you should be able read encoder data calling the Read Encoder Position.flx. When you are running on encoder as your primary feedback, you should be able read analog data calling the Read ADC.flx. If you do the enabling/disabling properly when you are switching from one feedback mode to other, you should be able to read all the signals.
Hope this helps!
Regards,
Yusuf C.
Applications Engineering
National Instruments

Switching from analog feedback to encoder feedback

Greetings,
I am having problems with switching feedback sources in my Labview App. I am using a 7344 board. I initialize the board in encoder feedback as primary. Then I am able to switch to analog feedback, but then the problem is when I switch back to encoder feedback it acts like it is still using analog feeback as a Primary. I can only get it back to encoder feedback only if I reinitialize the controller. I am disabling the axis before I am making config changes and then re enabling axis to run axis on both accounts. However it doesn't seem to be getting back to encoder feedback. Any Ideas?
Wade

Hey wade,
As mentioned in this Forum Thread, you should be able to switch back and forth between feedback sources on the 733X motion controller by disabling/enabling the axis. However, this is what you say you are doing. Perhaps changing the order in which you make the feedback switch. What happens if you make the feedback change and then simple disable/enable the axis? Are you seeing this same behavior on all of your axis? What version of the NI Motion driver are you using?
Hope this helps.
-Ben
WaterlooLabs

Problem using Toshiba Software Installer for Win 7 on Satellite L750-1MT

Hello!
I have problem using Toshiba Software Installer for Win 7 on Satellite L750-1MT (PSK30E-02T002B3) with no OS preinstalled.
I do the following:
1. Install Windows 7 x64, SP1.
2. Install LAN driver (device was not recognized by Windows 6) (downloaded from [http://se.computers.toshiba-europe.com/innovation/jsp/supportMyProduct.do?service=SE&LNG=26&userAction=S MP_RESULTS_PAGE&partNumber=PSK30E-02T002B3&serialNumber=&USER_ACTION=Serial%20number])
3. Install all Windows Updates from Microsoft
4. Run Toshiba Software Installer for Win 7 - it installs a couple of drivers and then asks to reboot.
Here is the log file for the first try (win7update.log):
Update started 12\28\2011 at 21:11
Installed TVALZ_O.INF
Installed IO & Memory Access Driver
driver_bluetooth_TC00241200A.exe /s /log /test has been installed with the result code of PASS
util_tvap_TC00215000H.exe /s /log /test /wait15 has been installed with the result code of PASS
Update completed at 21:29
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Update started 12\28\2011 at 21:38
Toshiba Bluetooth stack has already been installed.
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Thanks in advance!

You are right this notebook model was delivered without OS.
Win7 64bit is supported for this notebook model and all necessary drivers, tools and utilities are available on Toshiba download page.
What I can say is that all this stuff must be installed in right install order. I know it sounds stupid now but I recommend you to make clean OS again and continue installation following this installation order:
Win7 SP1
Intel Chipset SW Installation Utility 9.2.0.1015
TOSHIBA Supervisor Password Utility 4.8.6.0
TOSHIBA HW Setup Utility 4.8.6.0
TOSHIBA Bulletin Board V2.1.10
TOSHIBA ReelTime 1.7.17.0
Intel Management Engine Interface 7.0.2.1164
NVIDIA Display Driver 8.17.12.6669
Intel Rapid Storage Technology Driver 10.1.2.1004
TOSHIBA Value Added Package 1.5.4.64
USB3.0 Driver 2.0.32.0
NVIDIA HD Audio Driver 1.1.13.1
Conexant Audio Driver 8.51.1.0a
Intel Wireless LAN Driver 14.0.2.2.1.s64_wCAT
or
Atheros Wireless LAN Driver 9.2.0.206.0.s3264_wCAT
or
Realtek Wireless LAN Driver 2.00.0013
TOSHIBA Wireless LAN Indicator 1.0.3
Synaptics Touch Pad Driver 15.2.11.1
TOSHIBA Software Modem 2.2.97(SM2297ALS05)
Conexant Modem Driver 7.80.4.53
TOSHIBA HDD Protection 2.2.1.12
Atheros Bluetooth Filter Driver Package v1.0.7
Bluetooth Stack for Windows by Toshiba v8.00.04(T)
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TOSHIBA Web Camera Application V2.0.0.19
TOSHIBA Network Device ID Registry Setting Tool 3.0.32.4-14_wMSI
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TOSHIBA Media Controller Plug-in 1.0.6.1
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Please post some feedback.

Serious problem using FMS

Hello all
I have video chat application .When i do the chat there is a problem of echo/feedback (tat is i can hear my sound after 1 sec)-This is most faced when i use HP systems,Dell systems donot show this issue.
I doubt is there any configuration made in the audio driver.
Second issue is when the bandwidth is fluctuating the audio gets break and and a sudden replay of the previous video happens
(we are using VP6 for video encoding )
Please help me with this issue
Regards
Aravind

When experiencing feedback and echos the most common problem is the mic & speakers/headphones you use. Let every chatmember use headphones and see what happens. My guess is this will solve the problem. If one member uses speakers then the sound from everybody else will bounce back into the chat from these speakers. If your unable to use headphones for some reason try dedicated conference A/V equipment.
Using online chat will in most cases involve some unwritten rules. I belive one of them is trying to let only one person speaks at a time.
Hope that helps

Use analog input as sample clock

Hi,
I have a PCI 6115 DAQ card. I currently perform an
analog acquisition on ai0, with an external clock on PFI7. But
sometimes, my clock signal is not high enough and the acquisition does
not occur. At some NI show, I heard a trick to solve this problem :
plug the clock on analog input (say ai1), the clock signal gets
amplified by the card internal amplifiers, and then route this
amplified signal to the sampling clock. This seems to be a wonderfull
solution, but I cannot find out to actually redirect the amplified ao1
to the sampling clock. Does someone know how to do it ?
Thanks a lot,
Jérôme Lodewyck

I tested the attached example on a simulated device so hopefully it will work on a real one without any kinks. You didn't specify your programming environment, so I'm assuming you're using LabVIEW. If not, hopefully you can translate to the appropriate ADE based on the picture of the block diagram.
In the example, I'm using an AO task to program the analog trigger as specified. This has two consequences. First, you won't be able to perform hardware timed AO while the AI acquisition is running. If this isn't acceptable, you'll need to try the second approach described in the next paragraph. Second, you'll have to wire the signal to PFI0 instead of an AI channel. With this configuration, the signal will be seen with a +/- 10V range and referenced to AI Gnd. Since the trigger DAC is an 8 bit comparator circuit for this board, you'll have ~80 mV of resolution. You didn't mention what the amplitude or DC offset (if any) of your signal is, but hopefully this resolution will suffice. You can use the level and hysteresis properties for the analog trigger to filter out noise in the analog signal or account for DC offset.
If the constraints listed above aren't to your liking, you can try to use a second AI channel as a trigger channel. This has some advantages and disadvantages. The disadvantages are that this requires you to use a trigger with your AI task and it also requires you to acquire another channel of data. You mentioned the trigger wasn't a problem so this can probably be taken care of with simple analog start trigger. The data can easily be thrown away, but depending on your sampling rates, it might require a lot of extra bus bandwidth or processing power when scaling the data. On the positive side, it doesn't require you to use up your AO channels needlessly and you can apply gain to the input signal in order to effectively increase the resolution of the trigger circuit. You can also apply a low pass filter and different terminal configuration if desired. The gain, coupling, terminal configuration, filtering, and coupling applied to the signal is controlled by the values used in the Create Channel VI and the Channel Property node. To create an example that does this, simply start with one of the shipping examples for an Analog Start trigger, change the trigger source to one of the AI channels instead of a PFI or APFI pin, and change the clock source to the AnalogComparisonEvent as shown in the attached example.
That should do it. Good luck with your application and post back if you have additional troubles.
Attachments:
AI - External Clock Using Analog Trigger Circuit.vi ‏81 KB
AI - External Clock Using Analog Trigger Circuit.JPG ‏60 KB

Scaling Settings Analog Feedback for 7354

Hello,
I would like to use a Torque sensor as an analog feedback in 7354. The sensor range is +/- 100 Nm, The output is 10 VDC for 100 Nm and 0 VDC for -100 Nm so Zero Nm is 5 VDC.
How should I scale torque values as counts ? When I program with Labview, What should i do ?
Thanks
TallTale

Hello TallTale,
Thank you for using National Instruments discussion forums. Some more information might help in understanding what type of motion control system you have such as: Is your Torque related linearly to the position of the motor or are you changing the velocity due to the torque value? You can set the ADC range in Measurement and Automation Explorer for each axis analog inputs under "ADC Settings". The difficulty comes
in understanding the "paradigm shift" in the standard NI-Motion API
terms; specifically target position, velocity, acceleration, and
deceleration. I have attached a really good document that discusses how to setup your motion control system for analog feedback. I hope this information helps. Thanks and have a great day.
Regards,
Mark T
Applications Engineer
National Instruments
Attachments:
How to setup a system for analog feedback control.doc ‏1188 KB

Problem using analog feedback on pix7340

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